1. Technical Field
The present invention relates to a linear vibration motor.
2. Description of the Related Art
A vibration function of feeding-back call reception, call transmission, a key input state, or the like, to a user of a portable phone is an essential function of the portable phone. In order to implement this vibration function, a coin type/bar type vibration motor and a linear vibration motor have been mainly used. In the past, a function of simply feeding-back only the call reception has been used. However, in a current touch-type smart phone, as the vibration function has been used in an application such as a messenger, a game, or the like, a long lifespan and a fast response time have been required. In order to satisfy these requirements, most of the smart phones currently use the linear vibration motor.
The linear vibration motor is basically an actuator designed so that a weight and a spring structure supporting the weight have a specific resonance frequency and is driven by interaction between permanent magnets by receiving sine power approximate to the resonance frequency to a winding coil type electromagnet. The linear vibration motor should secure an internally sufficient space in which the weight may move to thereby be accelerated in order to maximize vibration force and be designed to have an externally slim size capable of satisfying the demand of customers (terminal manufacturers) for slimness.
Further, in order to stably apply power to a vibrator part, a printed circuit board should be fixed to a bracket. However, in a linear vibration motor according to the prior art including the following Related Art Document, in the case in which soldering is performed or a bonding material is applied in order to fix the printed circuit board to the bracket, a soldering flux or the bonding material is introduced into the vibrator part by a capillary phenomenon. In addition, a lift phenomenon is generated by the introduced flux or bonding material, such that touch sound of the vibrator part, that is, noise is generated.